[P.Johnston]

I believe I know the answer to this, but want your feedback.

I opened my case today and saw my cpu and system temps drop a good 2-3C. This indicates poor air circulation or not enough incoming (cool) air, right?

Here's the chart with no test/graphics:

Here's what I normally run idle with the system closed:

Should I add a 120mm fan on the side blowing at my Zalman heatsink?

Thanks in advance,
Paul

 

[Texican]

i can't find the link now but there was a topic on here where it was stated that you would actually want negative pressure when it comes to airflow. Basically, I believe this to mean that if you were to add a fan, make it an exhaust.

 

[Heru]

Sounds like you need more cowbell.

..and a 120MM exhaust fan. You can try intake, but I'd recommend exhaust.

 

[P.Johnston]

no kidding! exhaust? negative pressure in the case?

I was planning on adding a 120mm intake on the side, "on top" of the cpu heatsink, and a 120mm on the top exhausting.

 

[Texican]

yeah man, hang on, i'll keep looking for the thread that was run on here a few days ago.

 

[s1rrah]

Quote:

Originally Posted by P.Johnston no kidding! exhaust? negative pressure in the case? I was planning on adding a 120mm intake on the side, "on top" of the cpu heatsink, and a 120mm on the top exhausting.

Depends on the case, really.

My armor full tower, for instance, has only a top 120exhaust and a rear 92mm exhaust ... all the other fans, rear 120mm intake (flipped to blow into CPU cooler), dual 120mm front, 250mm side panel are intake.

I chose minimal exhaust with a lot of fresh intake due to the fact that the entire case, front, back, bottom and top is completely perforated either by wire mesh or holes ... therefore, negative pressure is pretty much impossible.

The case air temp, with the door on, is the same as my room ambient ... I've measured it many times ... therefore, the overall CPU/MB temps are identical whether the sidepanel is on or of.

In fact, some tests have shown my temps are better with the side panel on.

So regarding the negative pressure idea ... I think it will work best only with cases that will *allow* you to create negative pressure ...

 

[iampoor]

That could be the problem airflow but I believe that oping the side on even an antec 900 with 5 120mm fans and a 25cm fan will cause the same effect

 

[Texican]

http://www.overclock.net/computer-ca...gative+airflow

post # 14 is where to look

 

[Texican]

Quote:

Originally Posted by iampoor That could be the problem airflow but I believe that oping the side on even an antec 900 with 5 120mm fans and a 25cm fan will cause the same effect

English man, speak English.

 

[s1rrah]

Found an old drawing board illustration of the Armor fan setup I'm using.

This is totally non traditional, but after months of testing different configurations, it's the absolute best set up for CPU/MB temps I've hit upon.

And again, this only works because the Armor case is so 'full of holes' if you will ... the excess intake vs. exhaust is dealt with through spillover out of the cases comletely perforated construction ...

...

...

Just some ideas ...

 

[rottenotto]

That's a server case, isn't it? I think your plan for installing the 2 120's is a good one, with the intake on the lower fan, and the exhaust on the upper.What are your ambient temps ( are you at Pa State?)?

 

[P.Johnston]

Quote:

Originally Posted by rottenotto That's a server case, isn't it? I think your plan for installing the 2 120's is a good one, with the intake on the lower fan, and the exhaust on the upper.What are your ambient temps ( are you at Pa State?)?

AOpen HX08 is pretty much a server case. Large. Ambient temps...basement, cool. Probably close to 70-75. Need to check.

Yup. State College, PA. GO PSU!

 

[P.Johnston]

I turned all fans to exhaust, and my temps rose a bit.

System up 2C to 36C.
CPU up 6C to 43C idle.

I removed the side overnight and was surprised to see that my cpu was at 28C and my system temp read 29C. Yup--the Zalman CNPS7000A-Cu was cooling the CPU better than the system (north bridge?) heatsink (passive) was performing IDLE.

I fully believe, now, that if I install a beefy 120mm fan on the side door, directly on top of the CPU, that the Zalman will have enough fresh air to cool the entire system at least as well as "open case."

Thoughts?

-paul

 

[gonX]

I had the same CPU cooler as you a couple of weks back, and it loevs the intakes near it. I suggest you to fully load the system with an application like OCCT or Orthos, let it run for 10 minutes and see what your temps are like there.

 

[P.Johnston]

Quote:

Originally Posted by gonX I had the same CPU cooler as you a couple of weks back, and it loevs the intakes near it. I suggest you to fully load the system with an application like OCCT or Orthos, let it run for 10 minutes and see what your temps are like there.

I've already been through the Orthos / TAT tests. Just ran it again, based on your recommendation.

Case off, Orthos (cpu test), after 30m:
CPU: 61
Sys: 35

After that, I put the case back together (all fans exhaust). 5 minutes later, temps read:
CPU: 71
Sys: 33

I believe that my CPU h/s is starved for air with all exhaust. I also believe that a 120mm fan on the side blowing IN (with all others exhausting) will cool the case better than the front two (120, 80mm) blowing in.

-Paul

 

[Dezixn]

Why the hell did you put all fans on exhaust?

Didn't you state in the first post that you think you case needed more air?

So logically the only remedy for that is to put all fans on exhaust and starve your coolers of air

Negative pressure can mean all fans on exhaust, but when we use the term negative pressure in regards to cooling and such, we mean there should be be a greater amount of CFM from the exhaust fans than the amount of CFM from the intake fans.

 

[P.Johnston]

Quote:

Originally Posted by Dezixn Why the hell did you put all fans on exhaust? Didn't you state in the first post that you think you case needed more air? So logically the only remedy for that is to put all fans on exhaust and starve your coolers of air Negative pressure can mean all fans on exhaust, but when we use the term negative pressure in regards to cooling and such, we mean there should be be a greater amount of CFM from the exhaust fans than the amount of CFM from the intake fans.

I did it as a test, to see if I could pull the hot air out. No dice. Running open case now and temps never exceed 61C on the CPU (now running at 3.1 GHz). I am convinced now that I need a side fan--wish I had one of those new cases with a 120mm exhaust and a clear side with CPU and PCI vents. But I sure love the HX08, so it looks like it's time for another case mod!

-p